SVS-Vistek SHR 10GigE, Manual

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5.1.4 Color
Color cameras are identical to the monochrome versions. The color pixels are
transferred in sequence from the camera, in the same manner as the mono-
chrome, but considered as “raw”-format.
Fig.: 5-3: CCD with Bayer pattern
The camera sensor has a color mosaic filter called “Bayer” filter pattern named
after the person who invented it. The pattern alternates as follows:
E.g.: First line: GRGRGR... and so on. (R=red, B=blue, G=green) Second line:
BGBGBG... and so on. Please note that about half of the pixels are green, a
quarter red and a quarter blue. This is due to the maximum sensitivity of the
human eye at about 550 nm (green). De-Bayering is not done in the camera, it
must be done in the client software(also refer to SDK functions). Not all sensors
have the same sequence of color. The GenICam property PixelColorFilter indic-
ates the sequence of the color pixels when reading color images.
Using color information from the neighboring pixels the RG and B values of each
pixel is interpolated by software, e.g. the red pixel does not have information of
green and blue components. The performance of the image depends on the soft-
ware used.
Camera Link frame grabbers need information of the sequence order of the colors.
The order depends on sensor type. USB3 and GigE cameras provide this in their
XML file.
INFO It is recommended to use an IR cut filter for color applications
White balance
The human eye adapts to the definition of white depending on the
lighting conditions. The human brain will define a surface as
white, e.g. a sheet of paper, even when it is illuminated with a blu-
ish light.
White balance of a camera does the same. It defines white or
removes influences of a color based on a non-white illumination.
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Continuous: Auto white balance will analyze the taken images and adjust
exposure per color accordingly as long as the camera is taking images. Dif-
ferent colors of the same object in a sequence might be the result depending
on the other objects in the image
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Once: Auto white balance will adjust white balance as soon it is started and
will stop modifying parameters as soon white balance is finished.
5.1.5 Flip image
Images can be mirrored horizontally or vertically. Image flip is done inside the
memory of the camera, therefore not increasing the CPU load of the PC.
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